You create a melee weapon sized appropriately for you from opaque force.

You are considered proficient with this weapon, which acts in all ways as a masterwork weapon typical of its type. The instant weapon has hardness 20 and the same number of hit points as a typical weapon of its type. As a force effect, it can strike and damage incorporeal creatures. If the instant weapon leaves your hand at any time, the spell ends at the beginning of your next turn.